Windows Failed To Start: 0xc000000f Required Device Inaccessible?

I recently took on the task of replacing my motherboard, processor and computer case, going from an integrated AMD motherboard to an I7 processor and Gigabyte motherboard. Because my original case was too small, I bought a new case and moved everything over, hooking up everything I could in the process. While the BIOS work and most initial things seem fine, I cannot start Windows at all. I continuously get this error message telling me to repair my computer using my Windows 7 Instillation Disc. The problem is that my PC never came with one, and a Windows 7 Disc can be expensive. If anyone knows a simpler way to fix this problem, it would be appreciated. Thanks.